Drought Monitor: Isaac brings up to 7 inches of rain to Midwest

The Northeast: A fairly dry week over much of the region did not warrant any large-scale changes. Some rains late in the period did allow for some improvements over southern New York and north central Pennsylvania, where several counties were removed from D0 status and some improvements were made to D1 conditions. Lingering dryness over the short term did allow for some introduction of D0 conditions in northern Vermont this week.

Mid-Atlantic: Heavy rains, with some amounts approaching 12 inches, helped to ease some of the drought issues in the Delmarva region. Categorical improvements were made where the greatest amounts of rain occurred and other areas were adjusted throughout Maryland, Delaware, and Virginia. Short-term conditions throughout much of the area are recovering while long-term issues are lingering.

Southeast: As tropical storm Isaac sent some initial rain bands through the region, areas of south Florida picked up over 5 inches of rain. Since January 1, the Miami International airport has recorded 68.48 inches of rain, compared to a normal of 39.45 inches and 38.82 inches last year. With the last remaining areas of D0 conditions removed this week, this is the first time since June 29, 2010, that no abnormally dry or drought conditions are being depicted in Florida. Rains throughout much of eastern Georgia allowed for some easing of drought conditions there, and improvements were made to D3/D4 areas along the South Carolina coast. In North Carolina, D1 was eliminated and much of the remaining D0 was improved as well.

South: The Gulf coast of Louisiana as well as portions in east Texas continued in a wet pattern. At the end of the current U.S. Drought Monitor period, Hurricane Isaac was making landfall along the Louisiana and Mississippi coasts. The full impact of this storm and inland remnants will be considered next week for possible improvements.

Midwest: After a very dry summer, some areas have been in a wetter and cooler pattern over the last several weeks. Over the last week, the heaviest rains were recorded from northeast Kansas into southern Iowa and into central Illinois and northwest Indiana. Where the heaviest rains occurred, improvements were made, but it should be noted that many of the row crops will not benefit from these rains and pastures have had minimal improvement so far. Improvements were made in Michigan as an assessment of the impact of rains over the last several weeks allowed for the removal of D2 and a reduction of D1 conditions as well. Slight improvements were made over portions of southern Minnesota by removing the D3 from the southwest corner of the state while D1 was expanded in the central portion of the state.

The Plains: Another mostly dry week over most of the plains states. Areas of Kansas, extreme southeast Nebraska, and portions of Oklahoma did record precipitation amounts that approached 4 inches in places. In these areas, full categorical improvements were shown specifically in northeast and south central Kansas, southeast Nebraska and central Oklahoma. In North Dakota, dry conditions led to the expansion of D0 conditions in the western half of the state and D2 expanded in the southwest. In the northeast portion of North Dakota, D1 also expanded. In South Dakota, D3 expanded in the western portion of the state while D1 expanded in the north central. More water restrictions were going to take effect in Sioux Falls as the flow on the Big Sioux River was below 50 cfs. In portions of southeast Oklahoma, D4 was expanded to include more of the area that has been missing out on the recent rains. Even with rains in portions of Texas, the consensus was that the impacted grazing lands are not showing much change, so no improvements were made. Degradation was shown in west Texas into New Mexico where a new area of D4 was introduced. Conditions also intensified and expanded in south Texas where another new area of D4 was introduced and all drought intensity levels pushed farther to the north. Some improvements were shown to D0 and D1 levels in central and eastern Texas as the area was refined to account for the most recent precipitation in the area.

The West: The active rainfall pattern continued over portions of Arizona, western New Mexico and southern Nevada. Many locations recorded well over 2 inches of rain during the last week and some even over 3 inches. With the recent round of precipitation and a wet pattern for most of the month, categorical improvements were made over central Arizona, western New Mexico and southern Nevada. In southern Arizona, the D3 was completely eliminated. In Colorado, the dry conditions and impacts in the northeast part of the state allowed for the expansion of D4 out of Nebraska, and D3 expanded across much of southeast Wyoming and into Colorado. In southeast Colorado, D4 expanded where conditions continue to worsen. Some improvements were made in central and southwest Colorado where D3 was improved to D2, based upon recent rains.

In Wyoming, the last several months have continued to be dry and many of the indicators were worsening as well. For southwest Wyoming, D2/D3 was expanded to the east and north while D0 was introduced in the far northwest part of the state. Nevada had D3 conditions expand into more of the Great Basin and D2 expanded to the north to include portions of southern Oregon.

Hawaii, Alaska and Puerto Rico: No changes were made in Hawaii, Alaska or Puerto Rico this week.

Looking Ahead: Over the next five days (August 29-September 2) the remnants of Hurricane Isaac will continue to move inland and impact the area from Louisiana into Arkansas and portions of Missouri, Illinois, and Indiana. Areas of the Midwest may see up to 7 inches of rain as the system moves through the region. The southwestern United States looks to stay in an active pattern with scattered showers from Arizona up into Utah and Idaho. Temperatures look to be well above normal over much of the country, with departures of 6-9 degrees Fahrenheit over the High Plains.

The CPC 6-10 day forecast (September 3-7): Temperatures are expected to be above normal over most of the southern and eastern United States as well as through the Rocky Mountains, with portions of Alaska, the West Coast, and Midwest having a chance for below-normal temperatures. The best chance of above-normal temperatures is along the southern Plains and into the Southeast. The best chances for above-normal precipitation are in the Central Plains and into New England. Below-normal precipitation can be expected over the western United States and Texas.